fix: remove global network reference in bridge allowance handler (#6994)

## Explanation

<!--
Thanks for your contribution! Take a moment to answer these questions so
that reviewers have the information they need to properly understand
your changes:

* What is the current state of things and why does it need to change?
* What is the solution your changes offer and how does it work?
* Are there any changes whose purpose might not obvious to those
unfamiliar with the domain?
* If your primary goal was to update one package but you found you had
to update another one along the way, why did you do so?
* If you had to upgrade a dependency, why did you do so?
-->

Updates logic of `getBridgeERC20Allowance` method to use `chainId`
parameter to retrieve the `networkClient`.

## References

<!--
Are there any issues that this pull request is tied to?
Are there other links that reviewers should consult to understand these
changes better?
Are there client or consumer pull requests to adopt any breaking
changes?

For example:

* Fixes #12345
* Related to #67890
-->

## Checklist

- [ ] I've updated the test suite for new or updated code as appropriate
- [ ] I've updated documentation (JSDoc, Markdown, etc.) for new or
updated code as appropriate
- [ ] I've communicated my changes to consumers by [updating changelogs
for packages I've
changed](https://github.com/MetaMask/core/tree/main/docs/contributing.md#updating-changelogs),
highlighting breaking changes as necessary
- [ ] I've prepared draft pull requests for clients and consumer
packages to resolve any breaking changes

<!-- CURSOR_SUMMARY -->
---

> [!NOTE]
> `getBridgeERC20Allowance` now finds the network client via `chainId`
instead of the globally selected network, with new error handling and
tests, and changelog updated.
> 
> - **Bridge Controller**:
> - Use `#getNetworkClientByChainId(chainId)` to resolve network client
in `getBridgeERC20Allowance`, calling
`NetworkController:findNetworkClientIdByChainId` then
`NetworkController:getNetworkClientById`.
> - Add error handling: throw when no network client for `chainId` or
when no provider.
> - **Tests**:
> - Update `getBridgeERC20Allowance` tests to assert network client
lookup by `chainId` and new error cases.
> - **Changelog**:
> - Note fix for removing global selected network reference in
`getBridgeERC20Allowance`.
> 
> <sup>Written by [Cursor
Bugbot](https://cursor.com/dashboard?tab=bugbot) for commit
2239728. This will update automatically
on new commits. Configure
[here](https://cursor.com/dashboard?tab=bugbot).</sup>
<!-- /CURSOR_SUMMARY -->

---------

Co-authored-by: Micaela Estabillo <micaela.estabillo@consensys.net>
Co-authored-by: Micaela <100321200+micaelae@users.noreply.github.com>

Author: SteP-n-s

packages/bridge-controller/CHANGELOG.md

@@ -7,6 +7,10 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [Unreleased]
 
+### Fixed
+
+- Remove global selected network reference in `getBridgeERC20Allowance` handler ([#6994](https://github.com/MetaMask/core/pull/6994))
+
 ## [56.0.1]
 
 ### Changed

packages/bridge-controller/src/bridge-controller.test.ts

@@ -1306,28 +1306,71 @@ describe('BridgeController', function () {
         allowance: jest.fn(() => '100000000000000000000'),
       }));
 
-      messengerMock.call.mockReturnValue({
-        address: '0x123',
-        provider: jest.fn(),
-      } as never);
+      messengerMock.call
+        .mockReturnValueOnce('networkClientId-for-chain-0xa')
+        .mockReturnValueOnce({
+          // getNetworkClientById
+          address: '0x123',
+          provider: jest.fn(),
+        } as never);
 
       const allowance = await bridgeController.getBridgeERC20Allowance(
         '0x1f9840a85d5af5bf1d1762f925bdaddc4201f984',
         '0xa',
       );
       expect(allowance).toBe('100000000000000000000');
+      expect(messengerMock.call).toHaveBeenCalledTimes(2);
+      expect(messengerMock.call).toHaveBeenNthCalledWith(
+        1,
+        'NetworkController:findNetworkClientIdByChainId',
+        '0xa',
+      );
+      expect(messengerMock.call).toHaveBeenNthCalledWith(
+        2,
+        'NetworkController:getNetworkClientById',
+        'networkClientId-for-chain-0xa',
+      );
+    });
+
+    it('should throw an error when no network client is found for chainId', async () => {
+      // Setup
+      const mockMessenger = {
+        call: jest.fn().mockImplementation((methodName) => {
+          if (methodName === 'NetworkController:findNetworkClientIdByChainId') {
+            return undefined; // No network client found
+          }
+          return undefined;
+        }),
+        registerActionHandler: jest.fn(),
+        publish: jest.fn(),
+        registerInitialEventPayload: jest.fn(),
+      } as unknown as jest.Mocked<BridgeControllerMessenger>;
+
+      const controller = new BridgeController({
+        messenger: mockMessenger,
+        clientId: BridgeClientId.EXTENSION,
+        clientVersion: '1.0.0',
+        getLayer1GasFee: jest.fn(),
+        fetchFn: mockFetchFn,
+        trackMetaMetricsFn,
+      });
+
+      // Test
+      await expect(
+        controller.getBridgeERC20Allowance('0xContractAddress', '0x1'),
+      ).rejects.toThrow('No network client found for chainId: 0x1');
     });
 
     it('should throw an error when no provider is found', async () => {
       // Setup
       const mockMessenger = {
         call: jest.fn().mockImplementation((methodName) => {
+          if (methodName === 'NetworkController:findNetworkClientIdByChainId') {
+            return 'networkClientId-for-chain-0x1';
+          }
           if (methodName === 'NetworkController:getNetworkClientById') {
             return { provider: null };
           }
-          if (methodName === 'NetworkController:getState') {
-            return { selectedNetworkClientId: 'testNetworkClientId' };
-          }
           return undefined;
         }),
         registerActionHandler: jest.fn(),

packages/bridge-controller/src/bridge-controller.ts

@@ -779,6 +779,21 @@ export class BridgeController extends StaticIntervalPollingController<BridgePoll
     return networkClient;
   }
 
+  #getNetworkClientByChainId(chainId: Hex) {
+    const networkClientId = this.messenger.call(
+      'NetworkController:findNetworkClientIdByChainId',
+      chainId,
+    );
+    if (!networkClientId) {
+      throw new Error(`No network client found for chainId: ${chainId}`);
+    }
+    const networkClient = this.messenger.call(
+      'NetworkController:getNetworkClientById',
+      networkClientId,
+    );
+    return networkClient;
+  }
+
   readonly #getRequestParams = (): Omit<
     RequestParams,
     'token_symbol_source' | 'token_symbol_destination'
@@ -975,7 +990,8 @@ export class BridgeController extends StaticIntervalPollingController<BridgePoll
     contractAddress: string,
     chainId: Hex,
   ): Promise<string> => {
-    const provider = this.#getSelectedNetworkClient()?.provider;
+    const networkClient = this.#getNetworkClientByChainId(chainId);
+    const provider = networkClient?.provider;
     if (!provider) {
       throw new Error('No provider found');
     }